Top End???

[HondaRider07]

i have an '02 400ex and i want to get more top end out of it. i have a slip on white bros pipe, jetted, big gun rev box, and a k&n air filter. i know i could put a 440 kit in it but that reduces engine life. is there anything else that would give me more top end?

[Snipe]

Without doing engine work itself everything ya do is either gonna take away from bottom end and give to top end or take away from top end and give to bottom.

Its trying to find a happy medium. 1 thing you can do is go to a 16 tooth front sprocket or drop 2 teeth on the rear sprocket or both. The bigger the front sprocket and smaller the rear the faster you go. Bigger rear tires will also do the same.

[HondaRider07]

yea i kinda figured it would take away from the bottom end. are sprockets going to make a noticible difference? some people say they do and some dont?!?!

[bbender85]

have the head ported, higher compression piston, and a cam.. that'll bump you up pretty good, even with a stock or slightly over-bore.

[HondaRider07]

thanks for the advice

[F-16Guy]

If you want to do it cheaply and keep the reliability, install an OEM XR400R head gasket and a HotCams stage 1 cam. The XR head gasket will raise the compression slightly to offset any cylinder pressure loss from the cam, and the extra lift and duration will give you better power everywhere in the power band, but especially mid and top.

You could do just the cam, but once you get that far, you're only four bolts away from the head gasket, and it's only another $20 for the part, so why not?

[HondaRider07]

would a stage 2 hotcam make any more difference?

[BlasterEaten250]

Stage two is a top end cam stage one is a lowend cam.

[smelly$cat]

Sparks timing advance key?

[n811]

Put that 16 sprocket in first. its cheap. You will gain about 10-15 mph on the top end. Thats alot

[F-16Guy]

Originally posted by BlasterEaten250
Stage two is a top end cam stage one is a lowend cam.
Both cams make a huge difference in power everywhere, including top end. The stage 2 just pulls harder a little higher in the power band. I really like my stage 1. It still pulls like a tractor down low, but it has a ton of midrange, and the top end is much stronger than stock. Either cam will be a noticeable improvement, but if you're not going to run a high compression piston, a cam with more lift and less duration (stage 1) would be better.

[brokenmike]

Who says that a 440 kit reduces engine life????? My 440 has been togeather for over 6 years.... It still has great power and dont smoke.

[smelly$cat]

x2


Originally posted by brokenmike
Who says that a 440 kit reduces engine life????? My 440 has been togeather for over 6 years.... It still has great power and dont smoke.